Safe and effective dental treatment is indispensable for maintaining a good quality of life, particularly for the increasing numbers of the elderly in the population. Because of the many edentulous or partially edentulous patients, the need for removable partial and complete dentures has not declined. Metallic dentures are commonly fabricated using Co-Cr or Au-Pd alloys but the adverse effect of these metals to some patients (i.e., allergic reactions) has been increasing. One solution to this problem is to discontinue using these allergy- causing alloys and to replace them with titanium. Treatment with titanium prostheses has resulted in some clinical successes. Pure titanium [commercially pure titanium (CP Ti)] or titanium alloys containing aluminum, vanadium, or both, have been used until now. However, scientists have raised concerns about the biocompatibility of vanadium, so a more biocompatible titanium alloy is preferable. The overall objective of this proposed study is to examine the practicality of fabricating removable partial dentures from titanium alloys by studying certain characteristics necessary for sound, long-lasting prostheses. The three aims of the study are: 1) to determine the feasibility of fabricating sound removable denture frameworks cast from titanium alloys;2) to evaluate the retentive force and the attenuation of the retentive force of the clasp arms of the cast titanium alloy denture frameworks;and 3) to evaluate the resistance to fatigue and permanent deformation of clasps, occlusal rests, and base connector plates made of titanium alloys. For this present proposal, two titanium alloys, experimental Ti-5Al-5Cu and commercial Ti- 5Al-1Fe, were selected from a number of binary and ternary titanium alloys studied extensively at Baylor College of Dentistry during the last ten years. These alloys have a higher yield strength and a lower modulus of elasticity than conventional Co-Cr dental casting alloys, suggesting better performance when used to fabricate removable partial dentures. Conventional denture framework designs will be cast with these metals. The cast frameworks will be evaluated for completeness of casting using a visual defect ranking. X-ray radiography will be used to detect casting defects and porosity. The frameworks will also be checked for any dimensional changes during the casting process. Since the retention of the clasps is an important factor to prosthesis longevity, the stability of the retentive force of the titanium clasps will be evaluated, as well as the fatigue resistance and deformation of the clasps. The results of this study will be utilized as baseline information needed for a more extensive study in an R01 proposal of the application of titanium alloys to dental prostheses, including clinical trials. PUBLIC HEALTH RELEVANCE: Titanium is a very useful material for medical or dental purposes because it is benign in contact with the body. This study will investigate certain aspects of adapting titanium to the fabrication of removable partial dentures. Because of its biocompatible nature and low cost, the use of titanium and its alloys has the potential to benefit many people who require dental treatment with dentures.